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Personal Health: Facing Up to the Realities of Sleep Deprivation

By Jane E. Brody

Wake UP! This is National Sleep Awareness Week and judging from a national survey, Americans remain woefully ignorant about sleep, its critical role in their lives and the hazards of not getting enough of it.

How serious is this ignorance? These facts are telling:

While the average adult needs eight to nine hours of sleep a night, most get only seven, and nearly one-third of the 1,027 adults surveyed in late 1997 and early 1998 got six hours or less during the work week.

Two-thirds of those surveyed reported having a sleep-related problem, like insomnia, snoring or "restless leg syndrome," which causes involuntary twitching and muscular discomfort. But only 5 percent had consulted a physician or sleep specialist about it.

More than a third said they were so sleepy during the day that it interfered with their daily activities.

Twenty-three percent admitted to falling asleep at the wheel in the past year. The National Highway Traffic Safety Administration estimates that drowsy drivers are responsible for 100,000 crashes, 1,500 vehicular deaths and 71,000 injuries each year.

In addition, only 14 percent of those surveyed were able to pass a simple 12-question "sleep I.Q. test" developed by the National Sleep Foundation, a nonprofit Washington organization that supports research and education and sponsored the survey.

Myths and Misperceptions

A hard-working man I know once read that the brain needs only four hours of sleep a night, so he trained himself to sleep no more than that. But while you can teach yourself to sleep less, you cannot teach yourself to need less sleep. A person's sleep needs are biologically determined. Some people need only 6 hours a night, others need 10, but for most adults, at least 8 hours a night is required to function optimally.

In fact, before widespread use of the light bulb in the early 1900's and before distractions like television and the Internet, the average adult slept nine hours a night. And recent studies have shown that when all clues to time are removed and people are permitted to sleep as much as they choose, they sleep 10.3 hours out of every 24, just as monkeys and apes do.

WHAT'S YOUR SLEEP I.Q.?

You may spend eight hours a day doing it, but do you really understand it? Experts say a better understanding of sleep and sleep deprivation can help you make more effective use of your waking moments. Try your hand at this true-false test.

1. During sleep, your brain rests.

2. You cannot learn to function normally with one or two fewer hours of sleep a night than you need.

Dr. Stanley Coren, a neuropsychologist at the University of British Columbia, has estimated that thanks to our "high-tech, clock-driven life style," Americans now accumulate a sleep debt that averages 500 hours a year. Dr. Naomi Breslau and her colleagues at the Sleep Disorder Center at Henry Ford Health Sciences Center in Detroit reported last fall that an increase in daytime sleepiness can be detected after a mere one-hour sleep loss. In a study of 1,007 young adults, these researchers found that the people most likely to be sleepy during the day were those who were unmarried and working full-time, those who snored and those with a history of major depression.

Although most people tend to minimize the effects of insufficient sleep as simply feeling a bit tired, studies of sleep-deprived people have shown that they are less efficient and more irritable. Those who accumulate a large sleep debt experience "attentional lapses, reduced short-term memory capacity, impaired judgment and the occurrence of 'micro sleeps,' " Dr. Coren said.

If you happen to be driving during a microsleep, which lasts 10 to 60 seconds, there is ample time to get into a serious and possibly fatal accident. Drowsy drivers can fall asleep at the wheel with little or no warning. Drowsiness can also result in industrial accidents, decreased productivity and interpersonal problems.

Simply resting is not an adequate substitute for sleep. If you get sleepy when you are bored or sitting quietly in a warm or dark room or trying to read or listen to a concert or lecture, you are sleep-deprived. The sleep foundation noted, "Boredom doesn't cause sleepiness, it merely unmasks it." Millions of Americans take costly naps in theaters and concert halls.

Based on biological rhythms, it is normal to feel sleepy between 1 P.M. and 4 P.M. and between 2 A.M. and 6 A.M. That afternoon lull, during which many Americans reach for a caffeine pick-me-up, is siesta time in many countries. You'd be better off reaching for a cot than a cup. An hourlong afternoon nap would go a long way toward conquering the national sleep debt, and even 15 or 20 minutes of sleep at midday can do much to restore alertness and efficiency. But sleep experts say that you cannot "store up" sleep and eliminate daytime sleepiness during the work week by sleeping more on weekends.

How to Sleep Better

The foundation offers these tips for the sleep-deprived: Avoid caffeine, nicotine and alcohol in the late afternoon and evening; exercise regularly, but do it at least three hours before bedtime; establish a relaxing bedtime routine like taking a hot bath or meditating; use your bed only for sleeping and sex, not for reading or watching television; get out of bed if you don't fall asleep within half an hour, go to sleep and wake up at the same time every day, even on weekends, and, if you have trouble falling asleep at night, avoid daytime naps.

Contrary to popular belief, adults do not need less sleep as they get older. But sleep in older people is often interrupted by a need to use the bathroom, pain and other discomforts of chronic illness. Those who sleep less at night have to sleep more during the day to make up for their loss.

For the millions of people with sleep disorders like insomnia, loud snoring and restless leg syndrome and people whose sleep cycles are out of phase with the demands of their lives, the foundation recommends seeking the help of a sleep specialist. Loud snoring, for example, can be a symptom of sleep apnea, a cessation of breathing that occurs many times each night and, often without the person realizing it, seriously disrupts sleep and causes extreme daytime sleepiness. Untreated sleep apnea can result in serious accidents, high blood pressure and sudden death.

There are sleep clinics at hundreds of medical centers throughout the country, and the foundation, at 729 15th Street NW, 4th floor, Dept. 8Z, Washington, D.C., 20005, can provide information on the location of accredited sleep centers. Sleep problems are treatable, and failing to treat them can be costly.

To draw attention to the problem, the foundation has declared Thursday National Sleep Day, and it urges all Americans to get eight hours of sleep that day. In addition, the foundation has designated 170 sites around the country and in Puerto Rico and Canada where people can go that day to learn more about sleep and consult briefly with a sleep specialist. To locate a site near you, call the toll-free number 888-NSF-SLEEP (673-7533). Information will also be available on the foundation's Web site: www.sleepfoundation.org.